Vito Peter Jokubaitis wrote on June 12, 1997
on the IETF mailing list:

MEMBERSHIP: The "little m" designation refers to non-governmental
(i.e., private sector) members of the ITU Sectors (e.g., AT&T and MCI
are "little m" members of the ITU-T). Only governments can be "Big M"
Members of the ITU (and of its Sectors). The "little m" designation is
proposed to be changed to "Sector Member," but this action is still
pending. The ITU Council admitted ISOC to "little m" membership in the
ITU Sectors (where the real technical work gets done anyway), not the
ITU, in 1995.

EXCHANGE OF INFORMATION: Regarding communications between the ITU-T
Study Groups and the IETF, an ITU-T Recommendation A.4, entitled
"Communication Process between ITU-T and Forums and Consortia," was
approved by the World Telecommunications Standards Conference (WTSC) of
the ITU-T on 10/19/96. This process includes a procedure for qualifying
a forum or consortium before establishment of a liaison relationship
with the ITU-T; the procedure addresses questions like the openness of
the forum's or consortium's standardization process. The qualification
procedure was used during the last so-called study period of the ITU-T
(1993-1996) to qualify, for example, the ATM Forum. When I checked with
the Chief Counsellor of the ITU-T very recently, I discovered that the
IETF has not been qualified under Recommendation A.4. He expressed the
view that there was no need to do so, since he believed that any input
to the ITU-T from the IETF could be made in the form of a contribution
(roughly equivalent to an Internet-Draft in IETF terminology) whose
source would be the ISOC. After we got off the phone, it occurred to me
that a few liaison statements have gone in both directions between IETF
working groups and ITU-T Study Groups, which is a strange way of
operating, since you don't normally communicate with one of your own
members by liaison statement. On the one hand it looks like the ITU-T
is treating IETF as a member and on the other hand as a standards forum.
Vito P. Jokubaitis